硅纳米晶体的低温共晶合金化制作及其表征

摘要

Taking advantage of the eutectic points of Au/Sb and Au/Si at low temperatures,silicon nanocrystals doped with Sb atoms are fabricated on the surface of silicon wafers after an alloying reaction around 400 ℃.Scanning electron microscopy demonstrates that there exist craters in the shape of an inverted pyramid and large amount of nanostructures inside craters on the wafer surface due to Au/Si alloying reactions.Raman scattering spectroscopy verifies that these nanograins largely possess a crystal-like lattice structure.Secondary ion mass spectroscopy reveals that the doping concentration of Sb in Si exceeds 2 × 1018 cm-3,surpassing the solid solubility of Sb in the bulk silicon crystal.This growth method is easy to imple ment with a low thermal budget,which potentially provides it the good compatibility with other microano fabrication processes.%利用Au/Sb和Au/Si共晶点温度较低的特点,通过在～400℃合金化的方法,在硅片表面实现了掺Sb纳米晶体的制作.扫描电子显微镜观察到了Au/Si合金化反应形成的倒金字塔形蚀坑以及纳米结构的存在,拉曼散射光谱证实这些结构主要是纳米尺度的晶体,二次离子质谱表明Sb在Si中的掺杂浓度大于2×1018 cm-3,超过了Sb在体晶硅中的固溶度.该纳米晶体的制作方法简单易行,热预算较低,和其他微纳器件制作工艺的兼容性较好.